Machine for metal-working.



W. F. HOSFORD.

MACHINE FOR METAL WORKING. APPLICATION FILED NOV. 22. 1916.

Patented Apr. 1,1919

3 SHEETSSHEET 1 l l h l k H I I l l I I l I l I L| Patented Apr. 1,1919. l

3 $HEETSSHEET 2-.

W. F. HOSFORD.

MACHINE FOR METAL WORKING. APPLICATION FILED NOV. 27, 1916.

1,298,718. Patented 1,1919..

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MIX/am Fffosford UNITED STATES PATENT OFFIC.

WILLIAM F. HOSFORD, 01? OAK PARK, ILLINOIS, ASSIGNOR TO WESTERN ELECTRICCOMPANY, INCORPORATED, 015 NEW YORK, N. Y., A CORPORATION OF NEW YORK.

MACHINE FOR METAL-WORKING.

Specification of Letters Patent.

Patented Apr. 1, rate.

Application filed November 27, 1916. Serial No. 133,606.

To all whom, it may concern:

Be it known that I, VILLIAM F. Hosronn, a citizen of the United States,residing at Oak Park, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Machines for Metal-Yorking, of which the following is a full, clear, concise, and exactdescription.

This invention relates to a machine for metal working, and moreparticularly to a machine of this type, such as a punch press or headingmachine, in which the metal is subjected to an improved process of electrical heating preparatory to hot pressing.

The art of forming metals in punch presses and heading machines wasmaterially broadened when it developed that the process of hot pressingwas practicable. Thus by utilizing the method of hot pressing, in whichthe metals are heated just prior to the forming operation to increasetheir plasticity, it was made possible to form intricate shapes in oneor two forming operations; whereas the same shapes for cold drawing orheading required an extended series of operations, by means of which themetal would be gradually drawn into the shape desired. However, themethod of hot pressing has been rather slow in its development due tothe difiiculties encountered in heating the metal parts prior topressing. This operation is ordinarily performed by heating the metalblanks in a furnace separate and distinct from the heading machine orpunch press and then transferring the heated blank with a pair of tongsfrom said furnace to the machine. Such a process is necessarily slow anddifficult of performance.

()ne object of this invention consists in the production of an improvedmachine for the electrical heating of the metal just prior to theforming operation. Said machine comprises improved means toautomatically feed, cut. heat, and form the metal whereby hot pressingmay be. placed on the same practical .basis now universally employed incold metal forming and drawing operations.

This a d other objects will become apparent from the followingdescription and the appended claims.

.The invention is illustrated in the accompanying drawings in which:

Figure 1 is a plan view of the complete standard form of heading machinein whicha roll of wire is automatically fed to the machine and formedinto the particular shape desired. It will be evident, however, that theinvention can be readily applied to any kind of metal working machine,such as .punch presses, etc., in which the heatlng of the metal justprior to the forming operation isdesirable. I

The machine as illustrated in the drawings comprises a base 10 on whichare mounted therbearings 11-andl 12 and in which is journaled the crankshaft 13. Mounted on the crank shaft 13 is the double crank 7, the cam6, the fly wheel 14, the cam surfaces 5, l5, and 16, and the wheel crank17. The crank shaft 13 also carries the crank actuated link 18 whichbrings the two pivoted parts 8 and 9 of a toggle mechanism into astraight line twice during each revolution of said crank shaft, therebystriking two blows for each revolution of said shaft. The operation ofthe toggle press is well known in the art and will, therefore, not bedescribed.

Connected to the forward element 9 of thetoggle mechanism is the movableram 19 which serves to actuate the heading punch 20. The ram 19reciprocates to and fro on suitable guide plates secured to the innerside of the lateral supports 23 and 2st of cover plates 21 and 22.

the base plate 10' and is protected by the The machine is fed from acoil of wire, not shown, the wire being guided through feed rolls suchas 25 and thence through the frame work of the machine, from where itpasses through the cut-off quill 26. Secured to the right side of themachine is the bracket 27 in which the slide 28 is reciprocated by meansof the connecting rod 29 secured to the wheel crank 17. The slide 28contains a cam groove 30 in which a roll 31 is fitted, said roll 31being rigidly secured to the cross slide 32. Consequently as the slide28 is reciprocated to and fro, the cross slide 32 will be given a.

lateral motion which is imparted to the cutoff or shearing knife 33located at the end of the cutter bar 34. A ratchet feed,. not shown,operated by the eccentric 6 and the rod 4 steps the roll 25 forward foreach revolution of the shaft 13 to advance the wire through the cut-ofiquill 26 to the feed stop 35, after which the cut-0E knife 33 isadvanced in the manner just described, severing the wire but retainingit on the cutoff blade by means of a spring transfer finger to bedescribed hereinafter.

Loosely and slidably fitted in a bracket 37 secured to the cover plate22 is an arm 36 which is fitted at its rear end with apin that rides ina cam slot inthe side of the cam 15. This arm 36 and its associated cam15 serve to move the heading punch 20 vertically, so that the twomovable dies 40 and 41 may be brought into roper alinement with thestationary die 42 for: the two blows of the ram resulting from eachrevolution of the crank shaft 13.

'A rod 43 secured to the cover plate 21 by brackets 44 and 45 carriesone terminal 46 of the electrical heating mechanism. The rod 43 isspring-pressed against the surface of the cam 16 by means of the spiralspring 47. The cam 16 is so designed that it will press the rod 43forward to hold the blank 48 between the electrical terminals 46 and 49of the heating element when. said blank is transferred from the cut-offquill by means of the cutter 33 and the transfer finger as hereinafterdescribed. A spiral spring 50 serves to interconnect the two sections ofthe rod 43 and functions to limit the pressure exerted by the heatingterminal 46 in the operation of holding the blank 48 between the twoterminals 46 and 49 of the electrical heating mechanism.

The method of transferring the wire from the cut-off quill 26 to theheating terminals 46 and 49 is illustrated in detail in Figs. 4 and 5.As the knife 33 advances and severs the wire, the portion cut off isretained on the cut-off blade by means of a spring finger 51. Thepurpose of the finger 51 is to back up the cut-off blade when severingthewire and to assist in transferring the blank to the heatingterminals. The transfer mechanism, as indicated in Fig. 5, consists of acarrier 52 pivoted and actuated by an end bracket 53 which is bolted tothe end of the cut-off slide 32. At the operating end of the carrier 52is pivoted an arm 55 which is norquill 26 this finger is on the oppositeside of 7 the cut-off blade, being held there by the pressure of thespring encircling the rod 56. As the cut-off blade 33 advances, the wireis held against deflection at its outer end under the cutting pressureand is held perfectly square while the cut is being made. As the cutoffblade 33 advances with the blank toward the heating terminals thetransfer mechanism also advances and carries with it the blank securelyheld against the end of the cut-off blade 33 by means of the finger 51.The cutoff blade 33 and the finger 51 will thus carry the blank to aposition between the heating terminals 46 and 49. When the blank 48 ismoved into position between the heating elements by the transfer finger51, the rod 43 is pressed forward by the action of the cam 16 and theblank 48 is rigidly held in position between the heating elements 46 and49 under the compression of the spring 50 and against return movementfrom these terminals by a shoulder rovided therefor on each one thereof,as clearly indicated in Fig. 2. The pressure exerted by the rod 43 willinsure good electrical contact between the terminals 46 and 49 and theends of the blank 48. After a blank has been moved into this positionand is held therein, the cut-off slide 34 returns and the finger 51 ofthe transfer mechanism snaps back over the wire and is carried back upagainst a new length of wire which is advanced through the cut-off quill26.

Secured to the cut-off slide 34 is a second transfer finger 60. Thisfinger is pivoted at 61 and is equipped at its operating end with abifurcation consisting of the rigid finger 62 and the leaf spring finger63, between which the blank 48 will be rigidly held by the spring 63when the blank is pushed into place between said fingers. Since thecarrying arms 51 and 60 are both secured to the cut-off slide 34 theywill reciprocate to and fro in synchronism, and they are so located withrespect to the cut-off quill 26 and the heating terminals 46 and 49respectively that the finger 51 will transfer the blank from the cut-offquill to the heating terminals at the same time that the transfer finger60 is transferring the blank from the heating terminals to the operatingdies. When the blanks have been placed in their respective positions thetransfer fingers 51 and will snap back over the blanks in their returnmovement. The transfer finger 60, as clearly shown in Figs. 2 and 3,will move the blank 48 into position in front of the stationary die 42where the blank will be formed into the desired shape by the blowsstruck by the movable dies 40 and 41 and during a portion of whichperiod the knife 33 will cut off another blank from thefeed wire andanother blank will be submitted to the heating operation reparatory toforming.

When the blank has been formed to the desired shape by the dies 40, 41,and 42, the knock-out pin operated by the rod 66 pivoted at 67 andcontrolled by the rod 67 connected to the cam 5 will be moved forward todisplace the finished article from the stationary die 42. During theperiod that the pin 65 is moving forward the transfer fingers 51 and 60are moved laterally by the cut-off slide 32, transferring the blankcontained between the heating elements to the forming dies and the blankjust previously severed from the wire to the heating terminals.

The blank 48 is heated by insertion in a circuit of extremely lowresistance and heavy current carrying capacity, the amperage of thecurrent carried by the circuit depending upon the size of the part to beheated and the amount of heat desired. This circuit includes thesecondary 68 of a transformer 74, the terminals of which are wired bymeans of heavy copper leads 69 and 70 to the copper collars 71 and 72connected respectively to the heating terminals 49 and 46. The terminals49 and 46, as shown in Fig. 2, are embedded in electrical insulation,such as fiber or rubber, to insulate the heat in circuit from themachine proper. The primary 73 of the transformer 74 is adjust able sothat the amount of current flowing in the secondary circuit may bereadily controlled by rimary coil adjustment; the terminals of t eprimary 73 being connected to a suitable rotary switch 76 mounted on theshaft 13. This switch 76 is designed so that the period during which thecircuit of the primary is closed may be controlled by an adjusting screw75, the operating elements of the switch which close the circuit beingmounted on the shaft 13. This switch may be of any suitable desi inwhich the period during which the switch is closed may be readily timed,and in which means are provided for a quick make and break of thecircuit, so that the period during which the blank 48 is being heatedbetween the heating terminals 46 and 49 can be accurately controlled. Inthe preferred form of the invention a switch such as is described in myco-pendingapplication, Serial Number 52,514, filed Sept. 24, 1915, isused. The switch is connected to any suitable source of power such asthe generator 88.

. In order to prevent over-heating of the machine elements in which theblank is heated and formed, the dies 40, 41, and 42 and the heatingterminals 46 and 49 are water cooled. As indicated in Fig. 2, the dies40 and 41 are surrounded by the water cooling chamber 76', and the die42 by the water cooling chamber 77 these chambers being fed withcirculating water by the flexible hose connections 7 Sand 79respectively. The heating terminals 46 and 49 are surrounded by theWater cooling chambers 80 and 81 respectively, which chambers areconnected to the flexible hose connections 82 and 83 respectively, bymeans of which the water is continually circulated around the outerperiphery of the heating terminals, the

flow of the water being controlled by a suitable valve so that thetemperature rise of the terminals is under control.

The operation of the machine is as follows:

In the following description of the machine it will be assumed that "ablank has just been formed and ejected from the stationary die 42 inwhich condition the various operating elements of the machine will be inthe position as indicated in Fig. 1. Under these circumstances a lengthof wire will have been fed through the cut-off quill 26 and a blank suchas 48 will be held in position between the heating terminals 46 and 49.With these conditions prevailing, any further movement of the crankshaft 13 will cause the roll 31 to advance in the cam slot 30, and thiswill start the cross slide 32 in its lateral motion. This movement ofthe cross slide will advance the cutting bar 34 and the shearing knife33 which carry with them the transfer fingers 51 and 60. As the shearingknife 33 advances it severs the wire, and said knife in combination withthe transfer finger 51 will mOVe the severed end of the wire toward theheating terminals. At about this time, depending upon the temperaturerise desired for the blank, the contacts in the switch 76 will beclosed, thereby causing a flow of current through the secondary winding68 of the transformer 74 which includes the blank 48 held between theheating terminals. The current will be permitted to flow in thissecondary circuit until the blank has been heated the amount desired,and just prior to the time that the As the cutter bar 34 advances in itslat-- eral movement the bifurcated fingers of the transfer finger willmove into the path of the heated blank 48 and said blank will besecurelyheld between said fingers by theaction of the finger spring 63. As thetransfer finger 6O grasps the heated blank 48 the cam 16 will move to aposition so as to retract the rod 43 and hence the heating element 46,thus releasing the blank 48 for lateral movement. The cutter bar 34 willcontinue to move until it reaches its extreme left position, at whichtime the heated blank 48 will be in direct alinement with the stationarydie 42, and the severed blank held between the shearing knife 33 and thetransfer finger 51 will be in alinement with the slots in the heatingterminals 46 and 49.

Further revolution of the crank shaft 13 will then move the ram 19forward and this will advance the movable dies 40 and 41. At the sametime the rod 43 will be moved forward under the influence of the cam 16,which movement will rigidly position the blank held between the shearinknife 33 and transfer finger 51 between the heating terminals 46 and 49.As the ram 19 continues to move forward, the movable die 40 will strikethe blank 48 held in the transfer finger 6O and will push it into placein the stationary die 42, thus pushing back the ejecting pin which isfree to return to normal because the cam 5 has been turned by the shaft13 to such a position that the lever 66 and the rod 67 are also free toreturn to their normal positions.

The action of the movable die 40 upon the blank 48 will depend upon thedistance which it protrudes from the heading punch 20, and by properlyregulating this distance the die 40 may be utilized to merely insert theblank 48 in the stationary die 42, or to perform in addition to this anupsetting operation.

As soon as the blanks have been rigidly placed in position between theheating terminals 46 and 49 and the dies 40 and 42, the cutter bar 34will begin to move back to normal, due to the movement of thereciprocating slide 28. In this movement the cutter bar will carry withit the transfer finger mechanisms, the finger 51 snapping over the blankheld in position between the heating terminals and the transfer finger60 pulling away from the blank which is heldbetween the dies andlikewise snap-ping over the blank held between the heating terminals.The toggle movemen of the press will now pull back the ram 19, andduring this movement the rod 36 under the control of the cam 15 willshift the heading punch 20 so that the movable die 41 will be in directalinement with. the stationary die 42. Under the influence of the togglemechanism the ram will new again be moved forward and the blank will beformed in its final shape between the dies 41 and 42. The ram will thenagain be retracted and the ejecting pin 65 under the control of the cam5 will come forward to knock out the finished part, after which thecycle of operation as above enumerated will be repeated.

The invention as herein described is eX- ceedingly efiicient and usefulin the production of irregularly shaped articles and will produce thesame with a very great degree of accuracy and very rapidly. It will beevident that the invention may be applied to any type of mechanism inwhich it is desired to form exceedingly complicated and irregularlyshaped articles and that the invention is not restricted to the specificembodiment hereinbefore described, but is capable of many variations andapplications, without departing from its spirit and scope, as set forthin the appended claims.

What is claimed is:

1. In a device of the character described, the combination with astationary and movable die, of electrical terminals for heating ablankprior to forming it in said dies, a secondary circuit includingsaidterminals, said circuit being completed by said blank, a primarycircuit for ener izing said secondary circuit, and a switch associatedwith said primary circuit whereby the completion of said primary circuitwill be properly timed to prevent the flow of current in said secondarycircuit when the blank is being inserted or removed from said terminals.

2. In an electric heating device for hot pressing, the combinationwith'a stationary and a movable terminal, a secondary heating circuitincluding said terminals and said blank, means actuated to operate saidmovable terminal, means to deposit'the blank between said terminals, aprimary circuit for energizing said secondary circuit, and switchingmeans associated with said primary circuit whereby the time of currentable die. of means for feeding a strip of metal to the machine, meansfor cutting blanks from said strip, electrically operated meansincluding heating terminals for heating said blanks, positively operatedmeans for transferring said blanks from said outter to said terminals,and means for transvferring the heated blank from said terminals to saiddies.

4. In a device of the character described, the combination with astationary and mov- 5 able die, of means for feeding a strip of metal tothe machine, means for cutting blanks from said strip, means for heatingsaid blanks, means for transferring said blank from said cutter to saidheating means, and positively operated means for 10 transferring theheated blank from said heating means to said dies.

In witness whereof, I hereunto subscribe my name this 20th day ofNovember A. D.,

WILLIAM F, HOSFORD.

